title: Safety and tolerability of early noninvasive ventilatory correction using bilevel positive airway pressure in acute ischemic stroke.
abstract: OBJECTIVE
  Hypercapnia can induce intracranial blood-flow steal from ischemic brain tissues, and early initiation of noninvasive ventilator correction (NIVC) may improve cerebral hemodynamics in acute ischemic stroke. We sought to determine safety and tolerability of NIVC initiated on hospital admission without polysomnography study.
  
  
  METHODS
  Consecutive acute ischemic stroke patients were evaluated for the presence of a proximal arterial occlusion, daytime sleepiness, or history of obstructive sleep apnea, and acceptable pulse oximetry readings while awake (96%-100% on 2 to 4 L supplemental oxygen delivered by nasal cannula). NIVC was started on hospital admission as standard of care when considered necessary by treating physicians. NIVC was initiated using bilevel positive airway pressure at 10 cmH(2)O inspiratory positive airway pressure and 5 cmH(2)O expiratory positive airway pressure in combination with 40% fraction of inspired oxygen. All potential adverse events were prospectively documented.
  
  
  RESULTS
  Among 356 acute ischemic stroke patients (median NIHSS score, 5; interquartile range, 2-13), 64 cases (18%) received NIVC (median NIHSS score, 12; interquartile range, 6-17). Baseline stroke severity was higher and proximal arterial occlusions were more frequent in NIVC patients compared to the rest (P<0.001). NIVC was not tolerated by 4 patients (7%). Adverse events in NIVC included vomiting (n=1), aspiration pneumonia (n=1), respiratory failure/intubation (n=1), hypotension requiring pressors (n=1), and facial skin breakdown (n=3). The in-hospital mortality rate was 13% in NIVC patients and 8% in the rest (P=0.195). Neurological improvement during hospitalization tended to be greater in the NIVC group (median NIHSS score decrease, 2 points; interquartile range, 0-4) compared to the rest (median NIHSS score decrease, 1; interquartile range, 0-2; P=0.078).
  
  
  CONCLUSIONS
  In acute ischemic stroke patients with proximal arterial occlusion and excessive sleepiness or obstructive sleep apnea, NIVC can be initiated early with good tolerability and a relatively small risk of serious complications.
authors.affiliation: Comprehensive Stroke Center, University of Alabama at Birmingham Hospital, Birmingham, AL, USA.
authors.forename: Georgios
authors.initials: G
authors.lastname: Tsivgoulis
authors.forename: Yi
authors.initials: Y
authors.lastname: Zhang
authors.forename: Anne W
authors.initials: AW
authors.lastname: Alexandrov
authors.forename: Mark R
authors.initials: MR
authors.lastname: Harrigan
authors.forename: April
authors.initials: A
authors.lastname: Sisson
authors.forename: Limin
authors.initials: L
authors.lastname: Zhao
authors.forename: Mary
authors.initials: M
authors.lastname: Brethour
authors.forename: Luis
authors.initials: L
authors.lastname: Cava
authors.forename: Clotilde
authors.initials: C
authors.lastname: Balucani
authors.forename: Kristian
authors.initials: K
authors.lastname: Barlinn
authors.forename: Damon E
authors.initials: DE
authors.lastname: Patterson
authors.forename: Sotirios
authors.initials: S
authors.lastname: Giannopoulos
authors.forename: Jennifer
authors.initials: J
authors.lastname: DeWolfe
authors.forename: Andrei V
authors.initials: AV
authors.lastname: Alexandrov
mesh_terms: D000208:Acute Disease; D000368:Aged; D002545:Brain Ischemia / Q000150:complications / Q000401:mortality / Q000628:therapy*; D042241:Early Diagnosis; D005260:Female; D006801:Humans; D006935:Hypercapnia / Q000209:etiology / Q000401:mortality / Q000628:therapy; D008297:Male; D008875:Middle Aged; D011175:Positive-Pressure Respiration / Q000009:adverse effects* / Q000379:methods*; D020521:Stroke / Q000150:complications / Q000401:mortality / Q000628:therapy*; D013997:Time Factors; D016896:Treatment Outcome